First off, let me preface this by stating that I'm not now nor have I ever been a proponent of zero carb diets. I don't believe that they are necessarily unhealthy, but there are a lot of unanswered questions. The fact that so many feel great doing it leads me to believe that's it's probably fine, though I will say that it seems unduly stressful to combine ZC with any sort of glycolytic activity like resistance training, sprints etc. Hominins have been on a steady evolutionary march toward carnivory for millions of years. The real question is how close we got before the advent of the neolithic. Difficult to say, but I personally would want a more robust liver before going down the carnivore path. C'est la vie.
Now then, onto the meat of this post, as it were. I've noticed that most people choose a reduction in either carbs or fat in order to lose body fat. What I don't understand for those reducing carbs is why there is a see-saw effect with a concomitant increase in dietary fat. Gluconeogenesis is going to run on dietary protein (that you should be eating plenty of, otherwise it will run on muscle) and ketogenesis should run just fine on the uptake by the liver of circulating free fatty acids (and maybe VLDL-TGs as well).
My question then is for those who have been zero carb, have you tried high protein, low fat (basically just EFAs and the small amount of fat in a trimmed steak), low carb, and if so, did you feel worse doing it? I can't fathom how eating more fat would be advantageous unless maybe you were only eating more ketogenic fats like coconut oil, which might increase the manufacture of ketone-bodies. Even then, I kind of doubt that it's necessary. The liver should be manufacturing glucose and ketone-bodies based on need, so long as the substrates are available. An overweight person eating a lot of protein should be supplying the liver with all that is necessary to manufacture both. I wonder if not bothering with added MCTs would result in less ketone-bodies being excreted but supply the brain/heart with the same amount.
Seems to me that the worst approach is high fat, low protein, low carb since you'd be catabolizing muscle as well as unnecessarily eating fat that is being stored. Sure, the net result could be body fat reduction, but it would be slower than it needs to be and would probably plateau at a BF% that is much higher than desired.
Edit: Rabbit starvation as it's spoken of in the paleo community is a myth. It's probably a result of an essential fatty acid or other nutrient deficiency. And besides, if you are eating steaks that are remotely edible, they have a lot of intramuscular fat anyway, plus you add egg yolks for essential fatty acids. As such, a steak-based diet + yolks is plenty of fat, but it's a lot lower than most ketogenic diets. I'm speaking more of the active pursuit of added fat.
Protein from meat isn't toxic because the digestion is so slow and the amino acids (and thus, nitrogen) is liberated at a very measured pace. Not so with protein shakes/supplements however, the consumption of which I would never advocate.
asked byTravis_Culp (39821)
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on October 31, 2011
at 07:20 PM
Because you have to eat something, and eating only protein is impossible [rabbit starvation].
So it has to be fat.
You say you can't fathom how eating fat helps in weight loss, but the point is to practice beta oxidation pathways i.e. upregulate specific enzymes and make it efficient enough to provide enough energy for body needs. Body ditches stuff it doesn't use much, or downregulate them.
High protein input is toxic, while high fat input doesn't seem to be, even with PUFA in adequate context [i.e. low fructose, hi vitamin E and other].
Fat provides bunch of essential nutrients: A,D,E,K,Q10,ALA, and who knows what not, and those are some of the most important ones.
Using low carb, low fat diet = malnourishment unless you supplement like Kurzweil
=== EDIT ===
The diet in question is CR. Lets see:
Adult mammalian muscle flesh consists of roughly 75 percent water, 19 percent protein, 2.5 percent intramuscular fat, 1.2 percent carbohydrates and 2.3 percent other soluble non-protein substances
In 2011, the Scientific Advisory Committee on Nutrition published new energy recommendations. The new UK Department of Health Estimated Average Requirements (EAR) are a daily calorie intake of: 2079 calories per day for women (up from 1940) 2605 calories per day for men (up from 2550)
http://perfecthealthdiet.com/?cat=45 (I really need to check this)
At a protein intake of 230 g/day (920 calories), the body???s ability to convert ammonia to urea is saturated.  This means the nitrogen from every additional gram of protein lingers in the body as ammonia, a toxin.
So lets say caloric intake CI is 2000 cal. So, lest say zero carb, low fat, high protein diet is (C,F,P) = (10%,20%,70%) ratio of macronutrients.
10% C * 2000 CI = 200 kcal of carbs = 50g 20% F * 2000 CI = 400 kcal of fat intake which is 44g 70% P * 2000 CI = 1400 kcal of protein intake. 1400/4 = 350g of protein / 19% = 1842g of meat. 1842/3 = 614g of meat per meal.
Sounds doable for a single day or two, and still not zero carb [although if we subtract fiber it could be close] and Jaminet would consider this far into toxic zone (again, I really need to check this, I don't trust Jaminet). Calculation is not that precise, but it will suffice.
To be more realistic we would have to reduce calories to around 1000.
So it could be achieved, I don't think it could be sustained on the long run by majority of people and I need to check about toxicity, Travis may be even right on this.
on November 01, 2011
at 04:58 PM
This is a somewhat timely question for me. I've eaten high fat ZC for 2 years, but for the last week, I've practiced basically a PSMF. I've tried this a couple of times in the past 2 years, but never lasted more than a day for hunger. So this time I decided that rather than figure my protein needs by formula, to just eat low fat protein to satiation. I figure I'm eating between 700 and 1000 calories, and I'm feeling fine. I'm not hungry, tired, or foggy.
It turns out that I really need a lot of protein to feel best. Even experts disagree on the minimum. Moreover, most calculations don't include the extra you would need for gluconeogenesis, which is substantial if you eat no carbohydrate. Looking back, I realized that on my ad libitum 70% fat diet I was eating 2500-3000 calories, which comes out to a lot of protein, and that's when I realized how very much I would need to eat to properly be protein sparing.
Anyway, I'm doing this to try to address the last 10-15 or so pounds of fat that I seem to have settled with on my current diet. I've already lost 5. It's probably not a healthy strategy long-term, because of nutrients and absorption that fat helps with, and because it does exclude some important foods. Fortunately, at this rate it won't be necessary for very long. Presumably, it would also stop feeling good when fat stores are sufficiently low, too.
The most interesting part to me is that once again I'm going by hunger, not by a pre-computed numerical guess at what I need, and this seems to be a function of protein levels, since they are roughly constant no matter how much fat I'm getting.
on October 31, 2011
at 07:49 PM
This is where my lack of knowledge of physiology works to my advantage, I think. Since slashing my carb intake back in Sept 2009 to XLC/ZC levels, I've consistently found that I feel better when I eat more fat and less protein, although I have no really good theory as to why that would be. Both the anti-fat and pro-fat arguments seem logical in their own way to me, but my experience puts me in the pro-fat camp.
In the beginning I just took the standard advice and ate all the fat first, and added butter, too. About six months in I just found it hard to eat that much fat (it was around 75% when I put it in Nutritiondata.com), and my consumption just naturally dropped to around 65%, where it stays when I don't consciously fiddle with it. When I add HWC to my coffee, I get lots more energy, but as I wrote elsewhere today, it gives me a mild stomach ache.
A few months ago I tried giving up red meat in what turned out to be a short-lived experiment (I was trying to avoid Neu5gc to see if it would affect my autoimmune issues). I ate only fish and chicken and I avoided dairy since it came from cattle, which are the biggest source of Neu5gc. Bottom line: I felt like utter crap, and when I "cheated" by eating some fatty beef brisket my husband had smoked, I perked up like a houseplant finally getting some water.
When I calculated my numbers, though, I was shocked to see that not only had I been getting very little fat (maybe 30%, iirc), but I was eating around 900 cals/day. So it could have simply been insufficient calories on which to run my (admittedly mostly sedentary) body.
on November 01, 2011
at 11:32 AM
Yes and no.
No for weight loss. You'll get enough fat (IOW the EFA's) even from lean animal protein sources, and the rest comes from your own fat. This notion of eating fat for weight loss is physiologically misguided. Of course if it helps you stay on a plan to eat more fat, that's another story.
Yes for weight maintenance. In order to use protein for energy the nitrogen must be stripped from the molecule which is excreted as urea. I've seen many thresholds for theoretical maximum protein intakes. These are as low as 250g/day and as high as 400g/day. Even at 400g/day that's 1600 cal which will not be maintenance calories for many people, and although I do not believe LC will trash your kidneys, this much protein consistently will at least stress them. Therefore if you're not getting your energy calories from carbs, they must come from fat!
I think many here might find this study interesting: http://www.jbc.org/content/80/2/461.full.pdf
"According to their data the average daily food partition is about 280 gm. of protein, 135 gm. of fat, and 54 gm. of carbohydrate of which the bulk is derived from the glycogen of the meat eaten."
This works out to %F/P/C roughly 47/45/8 ... not nearly as high fat as many imagine.
on October 31, 2011
at 07:48 PM
I've had nothing but success with PSMFs... But I tend to only go there one week/month. When I do, I'll pretty much stick to 500-800 calories of seafood or lean fish. I don't tend to regain any weight I lose over the rest of the month, so that's a plus. I've never experienced anything close to rabbit starvation or really any signs that I was doing something unhealthful, but it's somewhat austere to spend the majority of your time eating like this, and probably not too realistic, as I don't intend to continue with the PSMF after I'm at a good weight.
on October 31, 2011
at 07:25 PM
Yes, I have tried very high protein very low fat. It was one of the first paleo-type diets I tried. And honestly, my keto adaption on that diet was worse. I felt weird and light-headed more often than on the higher-fat keto diet. Most keto-ers start out high protein because of fat fear and shift towards higher fat because it's more sustainable. But then again I was never very overweight, so maybe it's a different experience if you are.
Edit: I don't think you need to add fat your meaty diet either though, IF you are eating nose to tail and getting some fatty cuts in or eating reasonably fatty ground meat. I don't add heavy cream or coconut oil to my diet, personally, but I might if my only meat was chicken, turkey, or fish.
on October 31, 2011
at 08:53 PM
This is not a very scientific answer, but I, for one, am much less hungry on a high-fat, low-carb diet, versus a low-fat, low-carb (higher protein) diet. Being less hungry, or not hungry at all, allows me to stick with the low-carb, which is what gives me the best results for weight and fat loss.
on November 01, 2011
at 06:46 AM
I believe I might be able to give some useful input on this as I have dieted and weight trained my way down from 19% to <10% bodyfat.
First of all, when losing bodyfat, calories DO matter! Hence, you do need some form of caloric restriction in order to force your body to lose fat. There are basically three ways people go about this, 1) Not worry about macronutrient ratios and just count calories, 2) Eat high carb-low fat and count calories, and 3) Eat low carb-high fat and count calories.
The first two methods do produce fat loss, but they also produce some muscle loss and ravenous hunger if you keep on progressively reducing your calorie intake to achieve continued weight loss. I've found this to be true regardless of protein intake, which should ideally be kept high if you are dieting AND weight training.
The third approach, i.e. low carb with caloric restriction has the best effect on body composition. This is my opinion based on personal experience and I feel it is backed by most of the studies conducted by Jeff Volek.
Now, if you're low carbing for fat loss, it's different from low carbing in general where you only count carbs. Do count carbs and try to keep them in the range of 60-100g per day to meet the daily glucose needs of the body. Keep protein around 1.25g/lb of lean mass. Since you want to lose fat, start off with a calorie deficit of 600 calories. For example, if your maintenance calories are 2500, you will start off by eating 1900 calories where the fat calories will be what you get when you subtract your carb and protein calories from 1900. This should be your strategy if you want to lose a minimum of 1.5 lbs of fat per week. Use a 24 hr period on the weekend to carb up and replenish your glycogen stores since you're going to be weight training during the week. Make sure to eat around maintenance calories during your carb up to 'reset' your metabolism. It has to be high carb, low fat and moderate protein in order to prevent accumulation of bodyfat.
After one week, on the morning of your first carb up, monitor your fat loss to see if it's a minimum of 1.5 lbs. If yes, don't change anything for the second week. If it's less, decrease FAT INTAKE by around 15g. You don't want to be reducing carbs much, they should stay in the 60-100g range. To increase the calorie deficit, decrease fat intake and force your body to use more of your bodyfat for fuel. This increased calorie deficit is required because your body adapts to the new intake and reduces it's metabolism. If you want continuous fat loss, you need to progressively reduce your daily fat intake by about 15g, but only when your fat loss for the week is < 1.5 lb. Otherwise, keep everything the same.
The reason why PSMF is not a good long term strategy is because it will cause your metabolism to crash. You don't want that. When you get close to your goal and want to accelerate results, PSMF is a good idea but only for a max of 2 non-consecutive days a week. I used it sparingly myself but only when I got to around 12% bodyfat. Also, MCTs and Coconut oil are a very useful tool to encourage the body to burn fat at low bodyfat levels. You do need to count the calories though, as you would for any other calorie source. Simply adding them on top of your diet won't give you any fat loss benefit.
on October 31, 2011
at 09:22 PM
It's better than SAD, but fat is a very clean fuel so it's probably healthier to eat a moderate amount (under a pound per day) of meat and replace the rest of your carbs with fat. You don't have any huge muscle-gaining goals (and you don't need that much protein to build muscle anyway), you'll be getting plenty of nutrients from the meat you are eating, and fat is a lot cheaper. Lastly, fat makes meals taste better and helps you absorb nutrients.
Way I see it, you might not experience protein toxicity/nitrogen/ammonia/whatever from eating a ton of meat, but you definitely won't get it from fat.
on October 31, 2011
at 07:39 PM
I think it really depends on the person. An overweight person eating a high protein, low fat/carb diet may feel horrible and not lose weight if A) their body is bad at gluconeogenesis, or B) their body is bad at releasing and using fat as energy due to rarely using this pathway. For both of those points, I think both micronutrient deficiency (magnesium maybe?) and lack of physical activity may be the culprit. I'd say the first step in every weight loss plan is to become replete in all micronutrients and engage in plenty of lipolytic activity. Perhaps there should be an initial period of high fat intake (coconut oil) to encourage the body to switch to fat burning mode. Once the body is good at releasing and using fat, then it seems any dietary fat on top of body fat being burned could create a caloric surplus and stall weight loss. Once the desired weight is achieved, then bacon wrapped cheese covered with butter should be able to be eaten with no problems, since large amounts of stored body fat aren't being burned anymore and dietary fat calories are needed.
So to summarize, I think you're pretty spot on.
on November 01, 2011
at 06:16 AM
I was able to eat lean meats and veggies for three day shifts. This is VLC and not ZC. After three days it was tough to be social / think really clear. Later I added fat that allowed weeks of VLC with no ill effects.
on September 07, 2013
at 12:44 AM
I think you're right in that palatable meat generally has a decent amount of fat. Eating fat in isolation (say, by drinking heavy cream) is likely unnecessary even on a zero-carb diet.
on November 01, 2011
at 05:34 PM
PSMF without a doubt works, and works real well when done right. but the key to keeping it in balance is the real high carb-ups occassionally, which need to become more occassional the lower in bf you go. im a chick and it works so its gotta be 10 times easier for guys. make sure you hit some real nutrient dense foods a couple times a week and your set.
note- i dont do it anymore b/c it works 'too' well
on March 12, 2013
at 04:50 PM
Not at all. Or, at least not as high in fat as a lot here seem to think. The important thing is to make sure you're getting enough quality protein. Enough is a lot.
I don't live forever in a VLC diet (VLC for me means <50 grams of carbs from green vegetables..I primarily use broccoli and spinach), but I do cycle my carbs, and on VLC days I typically eat whatever amount of fat and protein comes out to be 4-6 whole eggs with spinach, a can of wild Alaskan pink salmon with broccoli, 1-2 scoops of whey protein post workout, chicken or flank steak with broccoli, a can of sardines, and 1% cottage cheese with a small handful of almonds before bed. I've been doing approximately that on my VLC days for years. Sometimes I leave out the almonds. Any more fat and there would be no point to going VLC, at least for me.
Now maybe it's different for people who live forever in VLC, but the days i eat carbs are little different besides including a bit of extra starch for refilling muscle glycogen stores and sometimes berries too. Now, when "bulking" (trying to gain substantial muscle) it's different, and I include a serving of starchy carbs at 4 meals a day and post workout protien shake with 2 cups of blueberries or some other sugary concoction.
The key is always to get a lot of quality protein in. I don't think people get nearly enough. Especially the girls on here that eat like 70% fat and less than 1800 calories a day.
on November 14, 2011
at 01:46 PM
hmm..can anyone point me to more info on PSMF? Any other good discussions around that might bring me up to speed? This is the first I've heard of it.
And Amber, so, you just ate more protein and ignored rough 'guideline' amounts given for women (which are what, by the way?)